PHP Arrays - Merge two arrays where a value is added together - php

Question

I need some more help regarding PHP Arrays and the issue I am having. I have an array like this: -
array(2) {
[0]=>
array(2) {
[0]=>
array(2) {
["count"]=>
string(3) "100"
["id"]=>
int(46)
}
[1]=>
array(2) {
["count"]=>
string(3) "300"
["id"]=>
int(53)
}
}
[1]=>
array(1) {
[0]=>
array(2) {
["count"]=>
string(3) "200"
["id"]=>
int(46)
}
}
}
However, I would like it to look more like this as array: -
array(2) {
[0]=>
array(2) {
["count"]=>
string(3) "300" <--- This has been added from Array 1 and 2
["id"]=>
int(46)
}
[1]=>
array(2) {
["count"]=>
string(3) "300"
["id"]=>
int(53)
}
}
Basically if the same id is in both areas I want the count number to be added to each other but if it's not then it needs to just be left alone and included in the array.
I have used a number of array functions such as array_merge and array_push but I am running out of ideas of how this could work. I have also started working on a foreach with if statements but I just got myself completely confused. I just need a second pair of eyes to look at the issue and see howe it can be done.
Thanks again everyone.

Answer 1

Should work with something like this:
$idToCountArray = array(); //temporary array to store id => countSum
array_walk_recursive($inputArray, function($value,$key) { //walk each array in data structure
if(isset(value['id']) && isset($value['count'])) {
//we have found an entry with id and count:
if(!isset($idToCountArray[$value['id']])) {
//first count for id => create initial count
$idToCountArray[$value['id']] = intval($value['count']);
} else {
//n'th count for id => add count to sum
$idToCountArray[$value['id']] += intval($value['count']);
}
}
});
//build final structure:
$result = array();
foreach($idToCountArray as $id => $countSum) {
$result[] = array('id' => $id, 'count' => ''.$countSum);
}
Please note that I have not testet the code and there is probably a more elegant/performant solution.

Answer 2

You could use something like this:
$end_array = array();
function build_end_array($item, $key){
global $end_array;
if (is_array($item)){
if( isset($item["id"])){
if(isset($end_array[$item["id"]]))
$end_array[$item["id"]] = $end_array[$item["id"]] + $item["count"]*1;
else
$end_array[$item["id"]] = $item["count"]*1;
}
else {
array_walk($item, 'build_end_array');
}
}
}
array_walk($start_array, 'build_end_array');
Here is a fiddle.

Answer 3

Thank you ever so much everyone. I actually worked it by doing this: -
$fullArray = array_merge($live, $archive);
$array = array();
foreach($fullArray as $key=>$value) {
$id = $value['id'];
$array[$id][] = $value['count'];
}
$result = array();
foreach($array as $key=>$value) {
$result[] = array('id' => $key, 'count' => array_sum($value));
}
return $result;